michael@0: /*
michael@0:  * auth.c
michael@0:  *
michael@0:  * some bookkeeping functions for authentication functions
michael@0:  *
michael@0:  * David A. McGrew
michael@0:  * Cisco Systems, Inc.
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  *	
michael@0:  * Copyright (c) 2001-2006, Cisco Systems, Inc.
michael@0:  * All rights reserved.
michael@0:  * 
michael@0:  * Redistribution and use in source and binary forms, with or without
michael@0:  * modification, are permitted provided that the following conditions
michael@0:  * are met:
michael@0:  * 
michael@0:  *   Redistributions of source code must retain the above copyright
michael@0:  *   notice, this list of conditions and the following disclaimer.
michael@0:  * 
michael@0:  *   Redistributions in binary form must reproduce the above
michael@0:  *   copyright notice, this list of conditions and the following
michael@0:  *   disclaimer in the documentation and/or other materials provided
michael@0:  *   with the distribution.
michael@0:  * 
michael@0:  *   Neither the name of the Cisco Systems, Inc. nor the names of its
michael@0:  *   contributors may be used to endorse or promote products derived
michael@0:  *   from this software without specific prior written permission.
michael@0:  * 
michael@0:  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0:  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0:  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
michael@0:  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
michael@0:  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
michael@0:  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
michael@0:  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
michael@0:  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
michael@0:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
michael@0:  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
michael@0:  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
michael@0:  * OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: #include "auth.h"
michael@0: 
michael@0: /* the debug module for authentiation */
michael@0: 
michael@0: debug_module_t mod_auth = {
michael@0:   0,                  /* debugging is off by default */
michael@0:   "auth func"         /* printable name for module   */
michael@0: };
michael@0: 
michael@0: 
michael@0: int
michael@0: auth_get_key_length(const auth_t *a) {
michael@0:   return a->key_len;
michael@0: }
michael@0: 
michael@0: int
michael@0: auth_get_tag_length(const auth_t *a) {
michael@0:   return a->out_len;
michael@0: }
michael@0: 
michael@0: int
michael@0: auth_get_prefix_length(const auth_t *a) {
michael@0:   return a->prefix_len;
michael@0: }
michael@0: 
michael@0: int
michael@0: auth_type_get_ref_count(const auth_type_t *at) {
michael@0:   return at->ref_count;
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * auth_type_test() tests an auth function of type ct against
michael@0:  * test cases provided in a list test_data of values of key, data, and tag
michael@0:  * that is known to be good
michael@0:  */
michael@0: 
michael@0: /* should be big enough for most occasions */
michael@0: #define SELF_TEST_TAG_BUF_OCTETS 32
michael@0: 
michael@0: err_status_t
michael@0: auth_type_test(const auth_type_t *at, const auth_test_case_t *test_data) {
michael@0:   const auth_test_case_t *test_case = test_data;
michael@0:   auth_t *a;
michael@0:   err_status_t status;
michael@0:   uint8_t tag[SELF_TEST_TAG_BUF_OCTETS];
michael@0:   int i, case_num = 0;
michael@0: 
michael@0:   debug_print(mod_auth, "running self-test for auth function %s", 
michael@0: 	      at->description);
michael@0:   
michael@0:   /*
michael@0:    * check to make sure that we have at least one test case, and
michael@0:    * return an error if we don't - we need to be paranoid here
michael@0:    */
michael@0:   if (test_case == NULL)
michael@0:     return err_status_cant_check;
michael@0: 
michael@0:   /* loop over all test cases */  
michael@0:   while (test_case != NULL) {
michael@0: 
michael@0:     /* check test case parameters */
michael@0:     if (test_case->tag_length_octets > SELF_TEST_TAG_BUF_OCTETS)
michael@0:       return err_status_bad_param;
michael@0:     
michael@0:     /* allocate auth */
michael@0:     status = auth_type_alloc(at, &a, test_case->key_length_octets,
michael@0: 			     test_case->tag_length_octets);
michael@0:     if (status)
michael@0:       return status;
michael@0:     
michael@0:     /* initialize auth */
michael@0:     status = auth_init(a, test_case->key);
michael@0:     if (status) {
michael@0:       auth_dealloc(a);
michael@0:       return status;
michael@0:     }
michael@0: 
michael@0:     /* zeroize tag then compute */
michael@0:     octet_string_set_to_zero(tag, test_case->tag_length_octets);
michael@0:     status = auth_compute(a, test_case->data,
michael@0: 			  test_case->data_length_octets, tag);
michael@0:     if (status) {
michael@0:       auth_dealloc(a);
michael@0:       return status;
michael@0:     }
michael@0:     
michael@0:     debug_print(mod_auth, "key: %s",
michael@0: 		octet_string_hex_string(test_case->key,
michael@0: 					test_case->key_length_octets));
michael@0:     debug_print(mod_auth, "data: %s",
michael@0: 		octet_string_hex_string(test_case->data,
michael@0: 				   test_case->data_length_octets));
michael@0:     debug_print(mod_auth, "tag computed: %s",
michael@0: 	   octet_string_hex_string(tag, test_case->tag_length_octets));
michael@0:     debug_print(mod_auth, "tag expected: %s",
michael@0: 	   octet_string_hex_string(test_case->tag,
michael@0: 				   test_case->tag_length_octets));
michael@0: 
michael@0:     /* check the result */
michael@0:     status = err_status_ok;
michael@0:     for (i=0; i < test_case->tag_length_octets; i++)
michael@0:       if (tag[i] != test_case->tag[i]) {
michael@0: 	status = err_status_algo_fail;
michael@0: 	debug_print(mod_auth, "test case %d failed", case_num);
michael@0: 	debug_print(mod_auth, "  (mismatch at octet %d)", i);
michael@0:       }
michael@0:     if (status) {
michael@0:       auth_dealloc(a);
michael@0:       return err_status_algo_fail;
michael@0:     }
michael@0:     
michael@0:     /* deallocate the auth function */
michael@0:     status = auth_dealloc(a);
michael@0:     if (status)
michael@0:       return status;
michael@0:     
michael@0:     /* 
michael@0:      * the auth function passed the test case, so move on to the next test
michael@0:      * case in the list; if NULL, we'll quit and return an OK
michael@0:      */   
michael@0:     test_case = test_case->next_test_case;
michael@0:     ++case_num;
michael@0:   }
michael@0:   
michael@0:   return err_status_ok;
michael@0: }
michael@0: 
michael@0: 
michael@0: /* 
michael@0:  * auth_type_self_test(at) performs auth_type_test on at's internal
michael@0:  * list of test data.
michael@0:  */
michael@0: 
michael@0: err_status_t
michael@0: auth_type_self_test(const auth_type_t *at) {
michael@0:   return auth_type_test(at, at->test_data);
michael@0: }
michael@0: